Suggested by Bruno Haible in:
https://lists.gnu.org/r/bug-gnulib/2020-05/msg00049.html
#define MAYBE_UNUSED _GL_ATTRIBUTE_MAYBE_UNUSED
#define NODISCARD _GL_ATTRIBUTE_NODISCARD
-/* Attributes from GCC have macro names beginning with 'ATTRIBUTE_' to
- avoid name clashes. */
+/* Selected GCC attributes; see:
+ https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html
+ These names begin with 'ATTRIBUTE_' to avoid name clashes. */
#define ATTRIBUTE_ALLOC_SIZE(args) _GL_ATTRIBUTE_ALLOC_SIZE(args)
#define ATTRIBUTE_ALWAYS_INLINE _GL_ATTRIBUTE_ALWAYS_INLINE
#define ATTRIBUTE_ARTIFICIAL _GL_ATTRIBUTE_ARTIFICIAL
/* Specification. */
#include <uchar.h>
-#include <attribute.h>
+#include "attribute.h"
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <stdbool.h>
-#include <attribute.h>
+#include "attribute.h"
#include <intprops.h>
#ifdef COMPILE_WIDE